5. Historically, Constantine's significance lies not in the fact that he was a Christian, personally, but that he for the first time endowed the new religion with that worldly power which made it for over one thousand years the most powerful moral, social, and political agency the world has seen. Constantine the Great was succeeded by Charles the Great, and he in turn by Otto the Great. On the ruins of the Christianised Roman Empire arose the Roman Empire of the Germans, and in this the work of Constantine was really completed. Not until the Reformation and the Modern Age did the cry arise that the work of Constantine must be undone. Constantine's three sons and successors continued his policy. Laws were passed favourable to Christianity. Paganism was still tolerated, but the tendency to suppress it had developed into a fixed policy. Sacrifices were forbidden on pain of death and confiscation in 352.[127:1] The persecuted, in turn, became the persecutors. "Emperors!" one of the Christian leaders advised, "the temples must be overthrown and utterly destroyed in order that the pernicious error may no longer pollute the Roman world. The Supreme God has committed the Government to you, so that you may cure this cancer." Pagan temples were converted into Christian churches. Unity of worship and unity of imperial rule were declared to be essential. Pagan opposition to religious unity under the Emperor was now interpreted as treason just as Christianity was so regarded before 311. Thus identified with the Empire, Christianity became the popular dominant faith. Rome and Alexandria alone clung to the old gods.[127:2] Under Julian (361-363), a nephew of Constantine the Great, paganism made one last supreme effort for mastery. The reaction was inspired by Neo-Platonism, by the personal devotion of Julian to the classical faith, and by the hope of securing a stronger imperial unity through the supremacy of paganism. Julian did not openly persecute Christianity, but treated it very much as Constantine did paganism. Had he lived longer, nevertheless, harsher measures might have been employed. He seemed to feel that he was swimming against the tide, however, and fell in battle against the Persians (363) saying, "Thou hast conquered, Galilean."[128:1]